Electronic calendars are in widespread use today with a variety of electronic devices to remind users of various upcoming events. Such electronic calendars allow a user to add, delete and edit entries which are stored in the electronic calendar document so that when the calendar is displayed on a display, the events appear in boxes that appear in the calendar for the appropriate day and time of the event. Thus, each day of such electronic calendars is typically divided into a plurality of time blocks, with each time block representing, for example, a fifteen minute, thirty minute, or one hour time period. Typically, the user is reminded by a signal, visual, audio or both, shortly before the event stored in the calendar is scheduled to occur. Such electronic calendars are in widespread use in various electronic devices, such as, for example, personal computers (PCs), portable laptop computers, personal digital assistants (PDAs), video cassette recorders (VCRs), and television set-top boxes or multimedia terminals, such as the Nokia Mediaterminal. The types of reminders that may be stored in such electronic calendars are limitless and include, for example, appointments, things to do, phone calls to make, television broadcast programs to watch or record, bills to be paid, etc.
One such electronic calendar that is in widespread use is the one that is part of the Windows Outlook computer program distributed by Microsoft. The Outlook program has a variety of versions of varying complexity that are used with a variety of electronic devices, primarily, computers and PDAs. In one version of the Outlook calendar program for use on a PC, the calendar entries can be shown in four settings. In the “Month” setting, each day is shown as a separate box and entries for each day are displayed within the box for that day, with each entry indicating the pertinent time. In the 7-day “Week” setting, seven boxes are shown and entries for each day are displayed within the box for that day, with each entry indicating the pertinent time. In the “Work Week” setting, five columns are shown, with the columns divided into half hour time blocks where entries are shown. In the “Day” setting, a single column for a single day is shown with the column divided into half hour time blocks for the display of calendar entries. For the “Day”, “Work Week” and “Week” settings a display of at least one month is displayed in a window of the display. Navigation through the Outlook calendar in the various calendar display settings may be accomplished with a point and click mouse (or similar device, such as a stylus or mouse touchpad) or by using arrow keys. For example, pointing and clicking on a particular time slot or box within a displayed day will bring the cursor to that time slot allowing the entry, viewing, editing or deleting of a calendar entry. Similarly, the arrow keys move the cursor through the calendar, with the particular movement for a particular arrow key being dependent on the particular calendar setting being used.
A disadvantage of the Outlook calendar is that it is designed to cover the entire area of the display (or at least a significant portion thereof if the calendar's display size is minimized to some extent), thereby obscuring a significant contiguous block of content shown on the display. Such obscuring of an entire block of the display prevents a user from observing what may be displayed beneath the calendar. Although this deficiency may not be so significant if the background display is static, such as if the background is displaying a word processing document, it is a clear disadvantage if the background display is dynamic, such as if the background is displaying a television or video program.
One electronic device user interface that is simple for a user to operate and also does not obscure a great proportion of the display is disclosed in PCT Patent Publication No. WO 00/65429. In accordance with that user interface, a display on or associated with the electronic device presents to the user a pair of intersecting cross-point navigation bars. At least one of these bars is scrollable, and each bar displays one or more object fields. By selectively scrolling one or both of the bars, one at a time, by pressing appropriate buttons on the electronic device or its remote controller, the user positions a particular object field, or selection, at the point where the two bars intersect. When the user depresses a “select” button, the displayed object field is selected, and either a bar of the display transforms to the selected sub-field, or the electronic device performs the action corresponding to the displayed object field selected, thereby adjusting or setting the electronic device in the desired manner. By pressing another button when a particular object field is at the intersection of the two bars, the level of the object field displayed in the entire corresponding bar is changed so that the user is given a group of choices that fall under the selected object field category. Thus, for example, if the vertical bar has six object fields (A, B, C, D, E, and F), the horizontal bar will show sub-fields corresponding to the object field positioned at the intersection of the two bars (F-1, F0, F1, F2, F3, etc.), as shown in FIG. 2a of the patent publication. If the user depresses a predefined navigation key, sub-sub-fields (F2:-1, F2:0, F2:1, F2:2, F2:3, etc.) corresponding to the sub-field (F2) positioned at the intersection of the two bars are then displayed on the vertical bar, as shown in FIG. 2b of the patent publication. In actual use, words descriptive of, for example, instruction categories or actual instructions to be transmitted to the electronic device are displayed to the user, not merely letters and numbers. Such listing and selection of sub- and sub-sub-fields can go down to as many levels as is necessary to provide the user with a desired selection of options. To navigate upward through the levels, a second predefined navigation key is depressed by the user, and, as a result, the visual content of the appropriate bar is changed to reflect a change in field level.
Although the user interface disclosed in PCT Patent Publication No. WO 00/65429 is fully able to permit a user to satisfactorily navigate among a plurality of possible instructions or device settings arranged in a plurality of groups, sub-groups, sub-sub-groups, etc., it may be somewhat difficult for a user to determine where in the menu hierarchy of possible instructions and groups of instructions he currently is so that he can easily navigate to another desired available electronic device instruction or setting, or group of such instructions or settings. This difficulty arises because only two levels of groups (or fields) are simultaneously displayed to the user. Whenever a group, sub-group, etc. is selected, the appropriate bar is overwritten by the sub-entries in the selected group or sub-group. Thus, no map is displayed showing generally where in the hierarchy of groups, sub-groups, etc. the user currently is located. As a result, a user unfamiliar with the hierarchy of the groups may be forced to randomly press the navigation buttons repeatedly, thereby navigating up, down and/or through the levels, until he has found the desired instruction or group of instructions, or a group of instructions or an instruction that is familiar to the user to enable him to navigate to the instruction or group of instructions actually desired.